Search

Wheat is one of the most important food sources on Earth. MicroRNAs (miRNAs) play important roles in wheat productivity. To identify wheat miRNAs as well as their expression profiles under drought condition, we constructed and sequenced small RNA (sRNA) libraries from the leaves and roots of three wheat cultivars (Kukri, RAC875 and Excalibur) under water and drought conditions. A total of 636 known miRNAs and 294 novel miRNAs were identified, of which 34 miRNAs were tissue- or cultivar-specific. Among these, 314 were significantly regulated under drought conditions. miRNAs that were drought-regulated in all cultivars displayed notably higher expression than those that responded in a cultivar-specific manner. Cultivar-specific drought response miRNAs were mainly detected in roots and showed significantly different drought regulations between cultivars. By using wheat degradome library, 6619 target genes were identified. Many target genes were strongly enriched for protein domains, such as MEKHLA, that play roles in drought response. Targeting analysis showed that drought-downregulated miRNAs targeted more genes than drought-upregulated miRNAs. Furthermore, such genes had more important functions. Additionally, the genes targeted by drought-downregulated miRNAs had multiple interactions with each other, while the genes targeted by drought-upregulated miRNAs had no interactions. Our data provide valuable information on wheat miRNA expression profiles and potential functions in different tissues, cultivars and drought conditions. [ABSTRACT FROM AUTHOR]

Ixodes ricinus ticks are distributed across Europe and are a vector of tick-borne diseases. Although I. ricinus transcriptome studies have focused exclusively on protein coding genes, the last decade witnessed a strong increase in long non-coding RNA (lncRNA) research and characterization. Here, we report for the first time an exhaustive analysis of these non-coding molecules in I. ricinus based on 131 RNA-seq datasets from three different BioProjects. Using this data, we obtained a consensus set of lncRNAs and showed that lncRNA expression is stable among different studies. While the length distribution of lncRNAs from the individual data sets is biased toward short length values, implying the existence of technical artefacts, the consensus lncRNAs show a more homogeneous distribution emphasizing the importance to incorporate data from different sources to generate a solid reference set of lncRNAs. KEGG enrichment analysis of host miRNAs putatively targeting lncRNAs upregulated upon feeding showed that these miRNAs are involved in several relevant functions for the tick-host interaction. The possibility that at least some tick lncRNAs act as host miRNA sponges was further explored by identifying lncRNAs with many target regions for a given host miRNA or sets of host miRNAs that consistently target lncRNAs together. Overall, our findings suggest that lncRNAs that may act as sponges have diverse biological roles related to the tick–host interaction in different tissues. [ABSTRACT FROM AUTHOR]

Few studies have examined tick proteomes, how they adapt to their environment, and their roles in the parasite–host interactions that drive tick infestation and pathogen transmission. Here we used a proteomics approach to screen for biologically and immunologically relevant proteins acting at the tick‐host interface during tick feeding and, as proof of principle, measured host antibody responses to some of the discovered candidates. We used a label‐free quantitative proteomic workflow to study salivary proteomes of (i) wild Ixodes ricinus ticks fed on different hosts, (ii) wild or laboratory ticks fed on the same host, and (iii) adult ticks cofed with nymphs. Our results reveal high and stable expression of several protease inhibitors and other tick‐specific proteins under different feeding conditions. Most pathways functionally enriched in sialoproteomes were related to proteolysis, endopeptidase, and amine‐binding activities. The generated catalogue of tick salivary proteins enabled the selection of six candidate secreted immunogenic peptides for rabbit immunizations, three of which induced strong and durable antigen‐specific antibody responses in rabbits. Furthermore, rabbits exposed to ticks mounted immune responses against the candidate peptides/proteins, confirming their expression at the tick‐vertebrate interface. Our approach provides insights into tick adaptation strategies to different feeding conditions and promising candidates for developing antitick vaccines or markers of exposure of vertebrate hosts to tick bites. [ABSTRACT FROM AUTHOR]

Ticks are blood-feeding arthropods that use the components of their salivary glands to counter the host's hemostatic, inflammatory, and immune responses. The tick midgut also plays a crucial role in hematophagy. It is responsible for managing blood meals (storage and digestion) and protecting against host immunity and pathogen infections. Previous transcriptomic studies revealed the complexity of tick sialomes (salivary gland transcriptomes) and mialomes (midgut transcriptomes) which encode for protease inhibitors, lipocalins (histamine-binding proteins), disintegrins, enzymes, and several other tick-specific proteins. Several studies have demonstrated that mammalian hosts acquire tick resistance against repeated tick bites. Consequently, there is an urgent need to uncover how tick sialomes and mialomes respond to resistant hosts, as they may serve to develop novel tick control strategies and applications. Here, we mimicked natural repeated tick bites in a laboratory setting and analyzed gene expression dynamics in the salivary glands and midguts of adult female ticks. Rabbits were subjected to a primary (feeding on a naive host) and a secondary infestation of the same host (we re-exposed the hosts but to other ticks). We used single salivary glands and midguts dissected from individual siblings adult pathogen-free female Ixodes ricinus to reduce genetic variability between individual ticks. The comprehensive analysis of 88 obtained RNA-seq data sets allows us to provide high-quality annotated sialomes and mialomes from individual ticks. Comparisons between fed/unfed, timepoints, and exposures yielded as many as 3000 putative differentially expressed genes (DEG). Interestingly, when classifying the exposure DEGs by means of a clustering approach we observed that the majority of these genes show increased expression at early feeding time-points in the mid-gut of re-exposed ticks. The existence of clearly defined groups of genes with highly similar responses to re-exposure suggests the existence of molecular swiches. In silico functional analysis shows that these early feeding reexposure response genes form a dense interaction network at protein level being related to virtually all aspects of gene expression regulation and glycosylation. The processed data is available through an easy-to-use database-associated webpage (https://arn.ugr.es/IxoriDB/) that can serve as a valuable resource for tick research., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Medina, Jmel, Cuveele, Gómez-Martín, Aparicio-Puerta, Mekki, Kotál, Martins, Hackenberg, Bensaoud and Kotsyfakis.)

Study Design: Validation of a translated, culturally adapted questionnaire., Objectives: To translate and culturally adapt the Spanish version of the Fear Avoidance Beliefs Questionnaire (FABQ), and to validate its use in Spanish-speaking patients with low back pain (LBP)., Summary of Background Data: The FABQ is a reliable evaluation instrument for fear avoidance beliefs, which includes two subscales (FAB-Work and FAB-Phys). No validated Spanish version was available., Methods: Translation/retranslation of the English version of the FABQ was done blindly and independently by a multidisciplinary team. The study was done in 12 primary care centers and 9 hospital outpatient clinics from seven regions in Spain, with 209 acute, subacute, and chronic patients who visited their physician for LBP: 53 in the pilot phase and 156 in the validation phase. Subjects were given the FABQ, two VAS for LBP and referred pain, and the Roland-Morris and SF-12 Questionnaires on their first visit and 14 days later. In the pilot phase, on day 1 test-retest reliability was estimated by giving a second FABQ in which the name and order of the items had been changed., Results: Time necessary to complete the FABQ was [median, P25, P75] 10 minutes (5,15). FABQ values were not normally distributed. Comprehensibility: No request for aid in interpretation was made during the validation phase and no item was left unanswered by >or= 10% of patients. Reliability: Scores [median, P25, P75] of the two FABQ were: 72.00 (47.25, 82.00) and 72.00 (49.50, 83.75), with an intraclass correlation coefficient of 0.9668 (95% confidence interval, 0.9421,0.9823). Mean of kappa values for all items was 0.743. Internal Consistency: Cronbach's alpha was 0.9337., Validity: Values of FAB and FAB-Work were >37% higher for patients on sick leave. For FAB-Phys differences were below 8%. FABQ, FAB-Work and FAB-Phys strongly correlated with disability on days 1 and 15., Conclusions: The Spanish version of the FABQ has good comprehensibility, internal consistency, and reliability. It cannot be analyzed parametrically, but only nonparametrically. The total FABQ is at least as valid as its subscales and simpler to score, making it more suitable for routine clinical use.